The walk started outside City Hall and marched down to Courthouse Park, where entertainment and speeches began.
Fresno police were on hand but officers say they were not active participants and just putting their presence at the event.
Organizers say the walk is meant to only support those who work in law enforcement and was not political in nature.
"We're not here because of anything, or in retaliation to anything," Dan Payne said. "We're here simply to show our support and appreciation for all law enforcement."
Fresno County Sheriff Margaret Mims attended the event and Fresno Mayor-elect Jerry Dyer gave a speech.